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Using simulations to evaluate Mantel-based methods for assessing landscape resistance to gene flow
Mantel-based tests have been the primary analytical methods for understanding how landscape features influence observed spatial genetic structure. Simulation studies examining Mantel-based approaches have highlighted major challenges associated with the use of such tests and fueled debate on when the Mantel test is appropriate for landscape genetics studies. We aim to provide some clarity in this debate using spatially explicit, individual-based, genetic simulations to examine the effects of the following on the performance of Mantel-based methods: (1) landscape configuration, (2) spatial genetic nonequilibrium, (3) nonlinear relationships between genetic and cost distances, and (4) correlation among cost distances derived from competing resistance models. Under most conditions, Mantel-based methods performed poorly. Causal modeling identified the true model only 22% of the time. Using relative support and simple Mantel r values boosted performance to approximately 50%. Across all methods, performance increased when landscapes were more fragmented, spatial genetic equilibrium was reached, and the relationship between cost distance and genetic distance was linearized. Performance depended on cost distance correlations among resistance models rather than cell-wise resistance correlations. Given these results, we suggest that the use of Mantel tests with linearized relationships is appropriate for discriminating among resistance models that have cost distance correlations <0.85 with each other for causal modeling, or <0.95 for relative support or simple Mantel r. Because most alternative parameterizations of resistance for the same landscape variable will result in highly correlated cost distances, the use of Mantel test-based methods to fine-tune resistance values will often not be effective.This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons, Ltd. The published article can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%292045-7758Keywords: landscape genetics, landscape resistance, landscape fragmentation, simulations, CDPOPKeywords: landscape genetics, landscape resistance, landscape fragmentation, simulations, CDPO
Improving Cosmological Constraints from Galaxy Cluster Number Counts with CMB-cluster-lensing Data: Results from the SPT-SZ Survey and Forecasts for the Future
We show the improvement to cosmological constraints from galaxy cluster surveys with the addition of cosmic microwave background (CMB)-cluster lensing data. We explore the cosmological implications of adding mass information from the 3.1 sigma detection of gravitational lensing of the CMB by galaxy clusters to the Sunyaev-Zel'dovich (SZ) selected galaxy cluster sample from the 2500 deg(2) SPT-SZ survey and targeted optical and X-ray follow-up data. In the ACDM model, the combination of the cluster sample with the Planck power spectrum measurements prefers sigma(8) (Omega(m)/0.3)(0.5) = 0.831 +/- 0.020. Adding the cluster data reduces the uncertainty on this quantity by a factor of 1.4, which is unchanged whether the 3.1 sigma CMB-cluster lensing measurement is included or not. We then forecast the impact of CMB-cluster lensing measurements with future cluster catalogs. Adding CMB-cluster lensing measurements to the SZ cluster catalog of the ongoing SPT-3G survey is expected to improve the expected constraint on the dark energy equation of state w by a factor of 1.3 to sigma(w) = 0.19. We find the largest improvements from CMB-cluster lensing measurements to be for sigma(8), where adding CMB-cluster lensing data to the cluster number counts reduces the expected uncertainty on sigma(8) by respective factors of 2.4 and 3.6 for SPT-3G and CMB-S4
Tinnitus: Distinguishing between Subjectively Perceived Loudness and Tinnitus-Related Distress
OBJECTIVES: Overall success of current tinnitus therapies is low, which may be due to the heterogeneity of tinnitus patients. Therefore, subclassification of tinnitus patients is expected to improve therapeutic allocation, which, in turn, is hoped to improve therapeutic success for the individual patient. The present study aims to define factors that differentially influence subjectively perceived tinnitus loudness and tinnitus-related distress. METHODS: In a questionnaire-based cross-sectional survey, the data of 4705 individuals with tinnitus were analyzed. The self-report questionnaire contained items about subjective tinnitus loudness, type of onset, awareness and localization of the tinnitus, hearing impairment, chronic comorbidities, sleep quality, and psychometrically validated questionnaires addressing tinnitus-related distress, depressivity, anxiety, and somatic symptom severity. In a binary step-wise logistic regression model, we tested the predictive power of these variables on subjective tinnitus loudness and tinnitus-related distress. RESULTS: The present data contribute to the distinction between subjective tinnitus loudness and tinnitus-related distress. Whereas subjective loudness was associated with permanent awareness and binaural localization of the tinnitus, tinnitus-related distress was associated with depressivity, anxiety, and somatic symptom severity. CONCLUSIONS: Subjective tinnitus loudness and the potential presence of severe depressivity, anxiety, and somatic symptom severity should be assessed separately from tinnitus-related distress. If loud tinnitus is the major complaint together with mild or moderate tinnitus-related distress, therapies should focus on auditory perception. If levels of depressivity, anxiety or somatic symptom severity are severe, therapies and further diagnosis should focus on these symptoms at first
Searching for Anisotropic Cosmic Birefringence with Polarization Data from SPTpol
We present a search for anisotropic cosmic birefringence in 500 deg of
southern sky observed at 150 GHz with the SPTpol camera on the South Pole
Telescope. We reconstruct a map of cosmic polarization rotation anisotropies
using higher-order correlations between the observed cosmic microwave
background (CMB) and fields. We then measure the angular power spectrum
of this map, which is found to be consistent with zero. The non-detection is
translated into an upper limit on the amplitude of the scale-invariant cosmic
rotation power spectrum,
rad (0.033 deg, 95% C.L.). This upper limit can be used to place
constraints on the strength of primordial magnetic fields, (95% C.L.), and on the coupling constant of the Chern-Simons
electromagnetic term (95% C.L.), where
is the inflationary Hubble scale. For the first time, we also
cross-correlate the CMB temperature fluctuations with the reconstructed
rotation angle map, a signal expected to be non-vanishing in certain
theoretical scenarios, and find no detectable signal. We perform a suite of
systematics and consistency checks and find no evidence for contamination.Comment: 17 pages, 7 figures - new subsection on non-Gaussian foregrounds,
conclusions unchanged - updated to match published version on PR
A Measurement of the CMB Temperature Power Spectrum and Constraints on Cosmology from the SPT-3G 2018 TT/TE/EE Data Set
We present a sample-variance-limited measurement of the temperature power
spectrum () of the cosmic microwave background (CMB) using observations of
a field made by SPT-3G in 2018. We report
multifrequency power spectrum measurements at 95, 150, and 220GHz covering the
angular multipole range . We combine this
measurement with the published polarization power spectrum measurements from
the 2018 observing season and update their associated covariance matrix to
complete the SPT-3G 2018 data set. This is the first analysis to
present cosmological constraints from SPT , , and power spectrum
measurements jointly. We blind the cosmological results and subject the data
set to a series of consistency tests at the power spectrum and parameter level.
We find excellent agreement between frequencies and spectrum types and our
results are robust to the modeling of astrophysical foregrounds. We report
results for CDM and a series of extensions, drawing on the following
parameters: the amplitude of the gravitational lensing effect on primary power
spectra , the effective number of neutrino species
, the primordial helium abundance , and the
baryon clumping factor due to primordial magnetic fields . We find that the
SPT-3G 2018 data are well fit by CDM with a
probability-to-exceed of . For CDM, we constrain the expansion
rate today to and the
combined structure growth parameter to . The SPT-based
results are effectively independent of Planck, and the cosmological parameter
constraints from either data set are within of each other.
(abridged)Comment: 35 Pages, 17 Figures, 11 Table
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